spinel

  1. Noun.  (mineralogy) any of several hard minerals of cubic symmetry that are mixed oxides of magnesium and aluminium and are used as gemstones of various colours.
  2. Noun.  (context, solid state chemistry) any crystalline material, not necessarily an oxide, that possesses the same crystal structure as this mineral.

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This entry was last updated on RefTopia from its source on 3/20/2012.